3.5l transplant from a 1989 E34

Sorry for the delay- just located a 1979 b7 Alpina garage find out of state and am trying to
find a home for it.

As for naming names on chips and problems - I learned my lesson on that one already...

For now I will just say that Motronic 1.3 and a 179 ecu are fine for me.
 
Just an idea-- Is it possible to group threads such as this into a "sticky"?

Lots of great information here (I've been pondering the swap myself), and having it in one place would be really great.
 
x_atlas0 said:
I generally prefer the MAF, because it is a direct sensor. The thing the DME needs is the mass of air entering the engine at any given time. The MAP sensor does this by providing the manifold average pressure, which can then be derived into the mass present in the manifold. The AFM provides a measurement of the air flow through the manifold, (namely, the volume of air, not the mass of air) which, when combined with the temperature of the air, is translated into the mass of air in the manifold. The MAF takes a direct measurement of the mass moving through it by finding the amount of power to keep a wire, or film at a certain temperature. The heat transfer through convection is dependent on the mass flow of air (namely by the velocity and density of the air through a set aperture) which is why it doesn't have to go through a bunch of signal conditioners and complex calculations to get the data the DME needs.

In terms of performance, the AFM is generally seen as the worst option, as it has poor throttle response and cannot be re-scaled very easily if you go turbo. (the door inside it will bang open, causing a temporary lean condition, other bad things) The MAP provides a nice balance of accuracy, cost, and transient response. The MAF is more accurate and has better responsiveness, but it is more costly and has a fairly set lifespan.

With the turbo 7-er, did you go with an aftermarket kit, (Miller, TCD, Cartech) or was it a 745 mash-up?
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Well put! +1
 
x_atlas0 said:
All M30 bellhousings work on any other M30. It should work just fine with the 3.5 if you are running a fuel system other than Motronic 1.0, which does require a special bellhousing.
Click to expand...

My apologies for hyjacking the thread but I am unclear on this point. The technical article pertaining to the transmission that is found in the Tech info section mentions removing the bellhousing from the four speed. It then ends the bellhpousing instructions?
Am I to understand that the bellhousing removed from the 4 speed is installed on the 265 Getrag 5 speed?

David
 
Bertocchi said:
My apologies for hyjacking the thread but I am unclear on this point. The technical article pertaining to the transmission that is found in the Tech info section mentions removing the bellhousing from the four speed. It then ends the bellhpousing instructions?
Am I to understand that the bellhousing removed from the 4 speed is installed on the 265 Getrag 5 speed?

David
Click to expand...

Motronic 1.0 gets its crank position information from the flywheel starter gear ring teeth, so it has a Hall effect sensor mounted on the bellhousing to get this information. Other stock FI systems get this information from other places, so you can use whatever bellhousing you want.

In general, you want to use the bellhousing that goes with the trans, as the 5-speed units also use a closed bellhousing, which keeps crud build up to a minimum. The stock 4 speed uses an external clutch slave cylinder with an external throw-out arm, which passes through a window in the bellhousing. I'm honestly not sure if you can splice a 4-speed bellhousing onto a Getrag 265, as I'd be concerned about the throw-out arm compatibility between the transmissions. The synchro activator probably doesn't line up between the transmissions.

Also, the slave cylinder design and implementation on the 265 and later is much easier to replace, as the cylinder is attached with some bolts, rather than a large (and usually rusty) snap ring. That bloody thing took me about 20 min to get off.

CookeD said:
Just an idea-- Is it possible to group threads such as this into a "sticky"?

Lots of great information here (I've been pondering the swap myself), and having it in one place would be really great.
Click to expand...

We had one for a while, but people kept asking swap questions anyway that were already covered. Very frustrating. We were also going to have an "Upgrade FAQ", much like the general one on the main website we have right now.
 
x_atlas0 said:
We had one for a while, but people kept asking swap questions anyway that were already covered. Very frustrating. We were also going to have an "Upgrade FAQ", much like the general one on the main website we have right now.
Click to expand...

Maybe start beating up on folks that are too lazy to "search" out the answer? Google "XXXX" site:www.e9coupe.com
 
x atlas,

This has been a hard winter here in Maryland. It has slowed me down a little. I have almost everything i need ,"question" I have headers that came from my sidedraft set-up. Where do I place the hole for the O2 sensor in the header or after?

cs1971
 
cs1971 said:
x atlas,

This has been a hard winter here in Maryland. It has slowed me down a little. I have almost everything i need ,"question" I have headers that came from my sidedraft set-up. Where do I place the hole for the O2 sensor in the header or after?

cs1971
Click to expand...

The stock placement in later cars is just before the cat. So, placing it after the collector should work fine.
 
X atlas,

I am now working on my fuel suppy. I picked up a CSI tank thinking it would solve the problem. I learned today from La Jolla Independent that I should have kept my old CS tank instead, they have an E30 conversion. Anyboby have some ideas to make what I have work?
 
Need help with starting now? I finally put the 3.5L Motronic together and it won't start. Fuel is not getting to the injectors. I found a clogged fuel canister at the pump. I took it out, now fuel is coming the regulator, test the fuel diaphram , it's opening. Removed the injector cover and when the key is in the on position , using my test light I have a light on the R/W and the Br/Y injector wires.:( The Br/Y should be GRD that goes to the Computer on pins 14 and 17 I think. Also, the pump only comes on when the engine is turning over. I thought the pump should briefly run with the key in the on position.

Can anyone help me trouble shoot this this before I replace the wiring harness
 
The pump should activate when the key is set to run, you can hear it whine from the cabin.

As for your issue, it sounds like you have an EWS problem, but the 89 MY 535 did not have EWS. How is the main relay working, and is the fuel pump relay working? Did you use the 1.3 harmonic balancer and crank position bracket+sensor? The car will not fire unless it knows where the crank is.

You may want to look for an E34 Bently manual, as it has all the wiring diagrams.
 
Did you try to bypass the fuel pump relay?
Or run 12v straight to the pump?
the last solution should be able to start the engine at least
 
I ruled out the crank sensor when I got a light from the V/GN wire coming from the wiring harness to feed the pump when turning the engine over. The fuel relay won't pass voltage unless it sees a signal from the crank sensor to the computer to the fuel relay. What do you think about seeing voltage on both wires that feed the injectors when the key is in the on position? I will run 12v straight to the pump and see what happens.
 
cs1971 said:
I ruled out the crank sensor when I got a light from the V/GN wire coming from the wiring harness to feed the pump when turning the engine over. The fuel relay won't pass voltage unless it sees a signal from the crank sensor to the computer to the fuel relay. What do you think about seeing voltage on both wires that feed the injectors when the key is in the on position? I will run 12v straight to the pump and see what happens.
Click to expand...

That is how it is supposed to be. The fuel injectors act like little solenoids, so they need a voltage difference to open. Since you don't want fuel spitting out of the injectors when you have the car set at "on", that is how it should be. If you hooked up an oscilloscope to the injector electric contacts, you'd see steps of various widths depending on how much throttle you gave it. That is because the injectors are controlled via pulse-width modulation, albeit inverted. (on-on is closed and on-off is open, while a normal system uses off-off for closed)

This may be a dumb question, but how are the fuses?

So you get voltage on the gn/vi wire coming from the fuel relay, that should come on when you have the key in the "on" position. Have you checked the fuel pump ground?
 
Diagnostic port?

One of the mistakes during my conversion was I wanted the wire harness to look clean and unobtrusive so I chose to remove the diagnostic plug from the harness; just doesn't look period correct with the plug in the engine compartment. What I didn't realize was there are two loop back connection in the cap for the plug and, if these are left open, the engine will start/run... After several weeks staring at schematics and scratching my head I figured out my mistake and made a new harness that incorporated the loop back connections. I was caught off guard when the engine fired right up.

Scott
 
Error...

Reading my post after posting I left an important word out...
Should say:
the engine will NOT start/run...
 
As a safety issue the fuel pump should not run with the key in RUN and the engine not turning over. The brown/white and brown/yellow wires are the ecu switched grounds to the injectors as is the green wire to the main relay as is the black wire to the coil as is the trigger wire to the fuel pump relay. Make sure your injectors are connected in the proper sequence- 1,3,5 and 2,4,6. After 600 rpm they will begin firing sequentially as long as the cylinder sensing wire is working on #6 plug wire.

I have done 5 of these conversions this year- send me a pm if you want a phone number.

Did you connect both green wires to switched power?
Did you run a dedicated black wire direct from the coil to the tach?
Do not use any black wires in the Motronic engine harness to the tach.
you should fuse the fuel pump wire [green violet 15 amps] and fuse the green wires- one is switched power for turning on the ECU and the other one is switched power to the coil.

Don
 
seems right

hi don,
what you describe makes perfect sense to me - it is not how my car works - my car is 3.5l w/ motronic 1.3, conversion done by carl for PO. the fuel pump runs continuously with key in run position and engine not running. this seemed wrong, and in fact unsafe to me. i called carl and asked him about this specifically, and he said that is the way its suppose to work???
 
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